The present invention relates to a new and distinct hybrid variety of Citrus L., which was obtained in May 1992, from the cross between the ‘KANKITSU OKITSU 46’ (mother plant, undisclosed breeding material) and the ‘HARUMI’ (father plant, Japanese Variety Registration No. 7506, registered on Nov. 25, 1999), which was carried out in Okitsu-town, Shimizu-ward, Shizuoka-city, Shizuoka-prefecture, Japan. The hybrid seeds were collected in November 1992, and immediately sown in a glasshouse to grow hybrid seedlings. The seedlings were grafted on satsuma mandarin inter-stocks in April 1994, and first fruits were observed in 1997.
After the first fruiting, tests for fruits quality were carried out on the above-mentioned individuals grafted on satsuma mandarin inter-stocks, and among these, No. P-92 was first selected as the best individual in 2005, based on its high brix and excellent fruits quality. The No. P-92 was phylogenetically named as ‘KANKITSU OKITSU 60’ (which was varietally denominated as ‘ASUKI’ at a later date), and subjected to the national trial in 29 test sites in Japan, from April 2006. As a result of the above-mentioned national trial, on August 2016, it was evaluated that ‘ASUKI’ matured around medium to late March, and had high brix and extremely excellent taste stably every year, in almost all the test sites.